Question:
I see there are "H", "M" and "E" in the Concerto part numbers that seem to indicate possible operating frequencies. Can you explain?
Answer:
H:
"H" indicates the high end devices.
Recall that the 28x can run up to 150 MHz. and the M3 is always limited to 100 MHz and is a divide down from the c28x clock (PLLSYSCLK) (Refer to Concerto College: System). Therefore these part numbers can run either with a maximum C28x clock or a maximum M3 clock:
| C28x | M3 |
| 150 MHz | 75 MHz |
| 100 MHz | 100 MHz |
M:
M is the mid-range device. The frequencies are limited to 75 MHz for both the C28x and the M3.
E:
At the low-end these devices are limited to 60 MHz for both the C28x and the M3.